Alright, so you have to pay shipping, but it's still cheaper than buying one elsewhere.
Udder Covers is offering a free nursing cover when you enter the promo code Breastfeeding at checkout. Shipping is $9.95. This is the one that I ordered.
Seven Slings is offering a free sling when you enter the same promo code, Breastfeeding, at checkout. Shipping is $11.95 with a optional size exchange insurance for $3.50. I'm not sure yet if I will order one, as we have a baby carrier already. Plus, I've been looking at the Moby Wraps... we'll see though! This is a great deal!